Junglepilot
Well Known Member
I am converting a 8A to 8 and removed the forward skins and FW to replace with new -8 skins.
That said, as I began to look at the reinstall I saw the note about sealants for the FW to floor skin. In the removal I found the previous builders sealants.
So I began looking at the options. The CS1900 is one that pops up a lot and several others that are Big$$. Of course, then there is simple red high temp RTV.
Next I spoke with several builders, one DAR and even Van's tech people.
Bottom line in my decision is this: The primary purpose of the seal is to keep out fumes that can incapacitate the pilot, not for fire protection primarily. That's what the mixture lever is for.
Then I found an interesting product from 3m called 3M CP 25WB+.
It is an intumescent meaning it expands when heated thus increasing it's [vapor] seal in a fire and is a "light char" intumescent. That means it also retards heat transfer. Both good for what this seal is supposed to do. In addition one of the primary ingredients is ground up fiberglass.
Of course other products may do a great job and have as many good features no doubt. Not saying it's the best thing available.
However the best is this: it'll do the job, it is not under hazmat and it is only about $ 12.00 for a standard 10 oz. tube (i.e size to fit in caulking gun) and is available at Home Depot/big box stores. All good things and a safe compromise when working on a $$ project like an RV-8. One of my favorite quotes about saving money is from Ben Franklin: "Watch the pennies and the dollars will take care of themselves"
At the end of the day, I am comfortable using this product.
Anyway I thought my decision process might be helpful to someone else. Found more than one thread on this all with many conclusions and ideas.
That said, as I began to look at the reinstall I saw the note about sealants for the FW to floor skin. In the removal I found the previous builders sealants.
So I began looking at the options. The CS1900 is one that pops up a lot and several others that are Big$$. Of course, then there is simple red high temp RTV.
Next I spoke with several builders, one DAR and even Van's tech people.
Bottom line in my decision is this: The primary purpose of the seal is to keep out fumes that can incapacitate the pilot, not for fire protection primarily. That's what the mixture lever is for.
- The problem I have with RTV is that silicone tends to draw moisture ( I flew in the Amazon rainforest for 8 years and saw that first hand). Also RTV can be somewhat corrosive to aluminum.
- The problem I have with the CS1900 is it is $60 for a tiny can. (product, hazmat fee, shipping)
Then I found an interesting product from 3m called 3M CP 25WB+.
It is an intumescent meaning it expands when heated thus increasing it's [vapor] seal in a fire and is a "light char" intumescent. That means it also retards heat transfer. Both good for what this seal is supposed to do. In addition one of the primary ingredients is ground up fiberglass.
Of course other products may do a great job and have as many good features no doubt. Not saying it's the best thing available.
However the best is this: it'll do the job, it is not under hazmat and it is only about $ 12.00 for a standard 10 oz. tube (i.e size to fit in caulking gun) and is available at Home Depot/big box stores. All good things and a safe compromise when working on a $$ project like an RV-8. One of my favorite quotes about saving money is from Ben Franklin: "Watch the pennies and the dollars will take care of themselves"
At the end of the day, I am comfortable using this product.
Anyway I thought my decision process might be helpful to someone else. Found more than one thread on this all with many conclusions and ideas.
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